Yosemite National Park: Dr. Fristrup, the senior acoustic Specialist with the National Park Service's Natural Sounds Program, talks about the effect of noise on predator-prey relationships, animal communications, and on human physiology.

Gateway NRA: Park ranger Dave Taft discusses various species of hawks and where they can be spotted in the Gateway National Recreation Area.

Natural Laboratory: Where have all the black abalone gone? How are scientists surveying the remaining population? Why are black abalones eating so much? Tune in for answers to these and related questions.

Natural Laboratory: Tune in to find out how deep-water corals are beneficial to an array of different marine organisms and the factors that could harm the corals. Information is provided by experts at the Cordell Bank National Marine Sanctuary.

Natural Laboratory: Due to higher carbon dioxide output, the oceans have become increasingly acidic. How is this acidity affecting marine organisms with shells? Tune in to find out.

Natural Laboratory: This audio file covers attracting great white sharks to boats so that they can be documented and tagged. They types of tags used are discussed as well as the migration patterns of the great white sharks found off the California coast.

Natural Laboratory: Why are populations of native Olympia oysters in Tomales Bay not recovering although they have not been harvested for nearly a century? Tune in to find out.

Natural Laboratory: Listen to this audio file to learn about Humboldt squid. In recent years these squids have been frequenting waters off of the California coast. Biologists search for the reason behind this unusual behavior.

Natural Laboratory: Tune in to learn about tracking Coho salmon and other fish species through electrofishing.

Natural Laboratory: What pollutants are present in harbor seals, how do the seals absorb these pollutants, and what testing is conducted to determine the level of contamination of the seals? Tune in to find out.